Add create glfw window as child support for win32

include/GLFW/glfw3.h

@@ -1129,6 +1129,7 @@ extern "C" {
 /*! @brief Win32 specific [window hint](@ref GLFW_WIN32_SHOWDEFAULT_hint).
  */
 #define GLFW_WIN32_SHOWDEFAULT      0x00025002
+#define GLFW_WIN32_HWND_PARENT      0x00025003
 /*! @brief Wayland specific
  *  [window hint](@ref GLFW_WAYLAND_APP_ID_hint).
  *  
@@ -3052,6 +3053,14 @@ GLFWAPI void glfwDefaultWindowHints(void);
  */
 GLFWAPI void glfwWindowHint(int hint, int value);
 
+/*! @brief Sets the specified window hint to the desired value.
+ * 
+ *  @since Added in version 3.4.x.
+ *
+ *  @ingroup window
+ */
+GLFWAPI void glfwWindowHintPointer(int hint, void* value);
+
 /*! @brief Sets the specified window hint to the desired value.
  *
  *  This function sets hints for the next call to @ref glfwCreateWindow.  The

src/internal.h

@@ -416,6 +416,7 @@ struct _GLFWwndconfig
     struct {
         GLFWbool  keymenu;
         GLFWbool  showDefault;
+        void*     handleParent;
     } win32;
     struct {
         char      appId[256];

src/win32_platform.h

@@ -413,6 +413,7 @@ typedef struct _GLFWlibraryWGL
 typedef struct _GLFWwindowWin32
 {
     HWND                handle;
+    HWND                handleParent;
     HICON               bigIcon;
     HICON               smallIcon;
 

src/win32_window.c

@@ -44,6 +44,8 @@ static DWORD getWindowStyle(const _GLFWwindow* window)
     if (window->monitor)
         style |= WS_POPUP;
     else
+    {
+        if (!window->win32.handleParent)
         {
             style |= WS_SYSMENU | WS_MINIMIZEBOX;
 
@@ -57,6 +59,9 @@ static DWORD getWindowStyle(const _GLFWwindow* window)
             else
                 style |= WS_POPUP;
         }
+        else
+            style |= WS_CHILD;
+    }
 
     return style;
 }
@@ -1384,13 +1389,14 @@ static int createNativeWindow(_GLFWwindow* window,
     if (!wideTitle)
         return GLFW_FALSE;
 
+    window->win32.handleParent = wndconfig->win32.handleParent;
     window->win32.handle = CreateWindowExW(exStyle,
                                            MAKEINTATOM(_glfw.win32.mainWindowClass),
                                            wideTitle,
                                            style,
                                            frameX, frameY,
                                            frameWidth, frameHeight,
-                                           NULL, // No parent window
+                                           (HWND)wndconfig->win32.handleParent,
                                            NULL, // No window menu
                                            _glfw.win32.instance,
                                            (LPVOID) wndconfig);

src/window.c

@@ -436,6 +436,18 @@ GLFWAPI void glfwWindowHint(int hint, int value)
     _glfwInputError(GLFW_INVALID_ENUM, "Invalid window hint 0x%08X", hint);
 }
 
+GLFWAPI void glfwWindowHintPointer(int hint, void* value)
+{
+    _GLFW_REQUIRE_INIT();
+
+    switch (hint)
+    {
+    case GLFW_WIN32_HWND_PARENT:
+        _glfw.hints.window.win32.handleParent = value;
+        break;
+    }
+}
+
 GLFWAPI void glfwWindowHintString(int hint, const char* value)
 {
     assert(value != NULL);